Patent GB-475745-A (GB)
Title: Improvements in or relating to lubricating systems
IPC: F16N25/02
Filed: 1936-05-27
Abstract: 475,745. Force feed lubricating. ARNOLD, C. (Farval Corporation) May 27, 1936, No. 14998. [Class 12 (iii)] [Also in Group XXVIII] A lubricating system comprises a lubricant reservoir, two feed and return conduit systems, measuring valves connected across said systems, pressure means for supplying lubricant to the conduit systems from the reservoir, a valve for directing the flow of lubricant alternately to the said conduits and for returning excess lubricant towards the reservoir, a second valve for controlling the movements of the first valve, and mechanism for retarding the movement of the second valve during the initial part of its travel and for accelerating its movement during the latter part of its travel. As shown, a pump 5 driven through gear 3 by an electric motor 1 delivers lubricant under pressure through a pipe 7 to the inlet of a reversing valve 8. A return pipe 9 leads back to the lubricant reservoir 6. Two leads of piping L<1>, R<1>, and L2, R2, issue from the valve 8 and are bridged by lubricators 10 each of which is connected to a bearing. In operation the valve 8 connects one lead of piping, say L2, R2 to the pressure pipe 7 and the other lead L<1>, R<1> to the return pipe 9. A measured quantity of lubricant is then discharged by each lubricator 10. The valve 8 then connects the piping L<2>, R<2> to the pipe 9 and the piping L<1>, R<1> to the pipe 7 so that the lubricators 10 are operated in the opposite direction to again discharge a measured quantity of lubricant. Means to delay successive operations of the lubricators 10 may be embodied in the system. In one arrangement a rod 37 associated with the valve 8 may actuate a switch to stop the motor 1 which is afterwards restarted by a time clock connected to the said switch. In an alternative means a chamber 80, Fig. 9, having a piston 82, the stroke of which can be varied, is connected to the pipings L<1>, R<1>; L2, R<2>; for the purpose of delaying the development of pressure in these pipes. The reversing valve 8 has a pair of piston valves 32, 39, Fig. 9. A rack on the valve 39 gears with a toothed sector 45 on a rock shaft 46, Fig. 5. The latter is connected by a lever 48 and spring 49 to an adjusting screw 53 to form a spring toggle so that initial sliding movement of the valve 39 is resisted and the final movement is accelerated by the spring 49. The pipings are connected as shown diagrammatically in Fig. 9. Lubricant from the pipe 7 is delivered to a nipple 55 and the pipe 9 is connected to the chamber of the valve 32 at two places. In the position shown the pipe L<1> is open to pressure lubricant and the pipe L<2> to the pipe 9. The valve 32 is held in position by oil pressure which passes to the left-hand side thereof through ports 78, 62. Oil from the nipple 55 passes through the pipe L<1> to the chamber 80 and moves piston 82 to the left, the oil on the left-hand side of the piston 82 being ejected through port 83 and pipes L2, 9, to the oil reservoir 6. When the piston 82 completes its stroke pressure builds up in the pipe line L<1> to actuate the lubricators 10. Pressure is then built up in the pipe R<1> and acts on the valve 39 to move it to the right. This cuts off the passage 62 and opens a passage 63 to the port 78 to force the valve 32 to the left. The piping L<2> is thus connected to pressure lubricant and the piping L<1> to the return pipe 9 and after the piston 82 has made a stroke to the right pressure is developed in the line L<2> to actuate the lubricators and then move the valve 39 to the left. A lubricator shown in Fig. 2, has a measuring chamber 11, a valve chamber 18 with a divided valve 19, 19<1>, a bearing connection 23 and nipples 20, 21, connected to the pipes L<2>, L<1>, respectively. In the position shown, the nipple 20 is under pressure and the nipple 21 is connected through pipe L<1> to the return pipe 9, and the piston 12 is faced by the oil pressure to deliver lubricant through the duct 16 to the bearing through the port 22. When the pressure system is reversed the valve 19, 19<1>, moves to the other extreme position and the piston 12 moves upwardly to deliver lubricant through the duct 17 to the port 22. The stroke of the piston 12 may be adjusted by screws 24, 25, and a rod 13 on the piston 12 gives a visual indication of the operation of the system. The lubricant pump shown in Fig. 7, is of the valveless type and has two plungers 92, 93, actuated by eccentrics on a shaft 98. The cylinder 90 of the plunger 92 has a suction port 99 open to the lubricant reservoir 6, and the plunger 92 discharges through a duct 100 to the cylinder 91 of the second plunger 93. U.S.A. Specification 2,007,156 is referred to.